Universal screw type lamp replacer



Aug- 29 w44 l H. D.. GRINNELL 2,357,104

UNIVERSAL SCREW TYPE LAMP REPLACER Fi1ed June 19, 1945` 2 sheets-sheet 1 Aug. 29, 1944. GR'INNEL; 2,357,104

UNIVERSAL SCREW TYPE LAMP REPLGER1 Filed June 19, 1943 2 lSluaelzs-Sheet 2 ArroR EYs Patented ug. 29, 1944 v UNITED sT..T1e;s` PATENT OFFICE Harold D. Grinnell, Pittsfield, Mass., assigner to The G. C. A. Manufacturing Co., Pittsfield, Mass., a corporation of Massachusetts Application lJune 19, 1943, Serial No. 491,426 l (Cl. 294-20) j 7 Claims.

This invention relates to lamp replacers intended for use where alamp is to be removed or replaced by rotation. The object of the ine vention is to provide a jaw construction capable of grasping firmly lamp bulbs of widely differing sizes and shapes. This is accomplished by providing a pluralityof jaws (preferably .three in number) which are pivoted to approach or recede from the sides of the lamp and which have grasping pads positioned to 4contact withrthe lamp bulb beyond its zone of maximum diameter; and in addition a jaw having a Contact pad movable with the yother jaws but in a direction along the axis of the lamp. As the lateral jaws close, thel axial jaw shifts towards the end of the lamp bulb, changing theA relative positions of the replacer and the bulb until the latter is firmly grasped between all four pads.

The manner in which this is `accomplished will best appear by reference to the accompanying drawings, in which Y Fig. 1 is an elevation of a replacer engaging a lamp bulb of relatively large size, the bulb being broken away to show a jaw at the rear;

Fig. 2 is a similar View looking from the left in Fig. 1;v

Fig. 3 is a View similar to Fig, 2 but showing the replacer in engagement with a bulb of small size; v

Fig. 4 is a similar viewshowing the replacer in engagement with a bulb of mushroom shape;

Fig. 5 is a section on line 5-5 of Fig. 1;

Fig. 6 is a section on line 6-6 of Fig. 1;

Fig. 7 is a detail illustrating the manner of assembly of the jaw pivots; and Y Fig. 8 is a detail showing one jaw in fully opened position.

The replacer is carried on a base I adapted, as is common in structures of this type, to be mounted in a holder at the end of a long jointed handle. To the top of the base is secured a journal member Il having pairs of spaced bearings |2 to receive pivot pins I3 on which the jaws I4 are mounted. The jaws may be of Wood or sheet metal, or of aluminum castings. The journal member nts upon dowel pins I and is held in place by a screw I6 extending into a wooden plug `II in the end of the base. Over the journal member, and also held by the dowel pins and screw, is a cap member I8 having lugs I9 extending over the ends of the pivot pins to retain them in position. This construction is described in more detail andis claimed in my copending application Serial No. 491,427 led concurrently herewith.

The jaws I4 in rotating on their pivot pins I3 are drawn by springs 20 in a direction to throw their upper ends outwardly, andatthe same time move abutments 2| inwardly so as to bear against a wedge cone 22 slidable on the upper end of the base l0. The cone rests `on a spring v23 compressibleV between it and a shoul# der 24, and may be drawn down against the `force of the spring by links 25 connected to a yoke 26 pivoted at one end to the basel and having at the other end a cord 21 by which the replacer may be actuated. As the cord is drawn down the cone 22 is lowered, permitting the jaws to be swung outwardly by the springs 20. On release of the cord the spring 23 will elevate the cone l22 and cause the jawsfto .be swung inwardly.

Each jaw carries, at a point beyond the zone of greatest diameter of the largest lamp to be handled, a pad 30 of some soft material like rubber or plastic. Pivoted to each jaw at 3| is a channel shaped link 32 having its end central portion cut away to embrace at one end the jaw and at the other a boss 33 on a vertically movable platform 34. This platform carries one or more pads 35 which contact the end of the lamp bulb. Due to the linkage connection with the jaws, the links always being kept on a slant of the central portion 36 of the link channel Vand a ypart 3'I of the jaw acting as an abutment (Fig. 8) the platform 34 rises as the jaws close. Whatever the size of the lamp being gripped, therefore, it will be raised in the jaws until it is in proper 'position to be held. This' is clearlybrought out by a comparison of Figs. 2 and 3. The replacer will handle all sizes of lamps from a 15 watt bulb to larger bulbs 5 or 6 inches in diameter.

To handle bulbs of different shape, such as the mushroom bulb 40 shown in Fig. 4, the jaws are provided with intermediate pads 4I and 42 which may be made of rubber tubing strung on a bent metal strip 43. These pads are so positioned as to make contact with the bulb on opposite sides of its zone of maximuml diameter.

What I claim is:

1. A lamp replacer comprising a plurality of jaws movable towards and away Ifrom the sides of a lamp bulb and having contact surfaces to engage the sides of the bulb above its zone of maximum diameter, a pad mounted for movement towards and away from the end of the bulb, and means for moving the pad towards the end of the bulb as the jaws approach each other.

2. A lamp replacer comprising. a base, a plurality of jaws pivoted to the base to swing towards and from a lamp bulb and having contact surfaces to engage the sides of the bulb abov its zone of maximum diameter, a pad, links connected between the several jaws and the pad and slanting from the jaws towards the end of the lamp, and means for opening and closing the jaws.

3. A lamp replacer comprising a base, three jaws pivoted to the base to swing towards each other and bowed outwardly to receive a lamp between them, three links each pivoted to one of the jaws and to a platform located between the jaws at a point between the end of the jaws and the pivotal connection of the links thereto, lamp contact pads located on said platform and on the ends of the jaws, said latter pads being located beyond the zone of maximum diameter of the lamps t0 be held, and means for opening and closing the jaws, whereby the platform will move towards Ythe end of the jaws as the jaws are closed `and will maintain in proper relation to the jaws lamps of all sizes within the range of the device.

4. A lamp replacer comprising a plurality of jaws movable towards and away from the sides of a lamp bulb and having contact surfaces to engage the sides of the bulb above its zone of maximum diameter, a pad mounted for movement towards and away from the end of the bulb, means for moving the pad towards the end of the bulb asthe jaws approach each other, and additional contact surfaces carried by the jaws between the first-named contact surfaces and the pad to grasp lamp bulbs of mushroom shape.

5. A lamp replacer of the type having a plurality of jaws pivotally mounted in a cluster for radial movement characterized by a pad located between the jaws and linkage connecting the pad and the jaws to move said pad towards the end of the jaws -as the latter close, said jaws having lamp contact surfaces positioned both beyond the zone of maximum diameter of a pear-shaped bulb and adjacent the zone of maximum diameter of a mushroom-shaped bulb.

6. A lamp replacer of the type having a plurality of jaws pivotally mounted in a cluster for radial movement characterized by a, pad located between the jaws andlinkage connecting the pad and the jaws to move said pad towards the ends of the jaws as the latter close, said jaws having lamp contact surfaces positioned beyond the zone of maximum diameter of a pear-shaped bulb.

'1. A lamp replacer comprising a base, three jaws pivoted to the base to swing towards each other and bowed outwardly to receive a lamp between them, three links each pivoted to one of the jaws and to a platform located between the jaws at a point between the -end of the jaws and the pivotal connection of the links thereto, lamp contact pads -located on said platform and on the others of the jaws, said latter pads being located beyond the zone of maximum diameter of the lamps to be held, means for opening and closing the jaws whereby the platform will move towards the end of the jaws as the jaws are closed and will maintain in proper relation to the jaws lamps of -all sizes within the range of the device, and contact pads on the jaws intermediate said pads on the jaw ends and said pads on the platform' to engage the zone'of maximum diameter of lamp bulbs of mushroom shape.

HAROLD D. GRINNELL. 

